In this study, three features of speedometer design were evaluated through two experiments. Especially, the
concept of dynamic speedometer using a fisheye view to show increased font size of current speed was developed
and evaluated. The results demonstrated, in general, similar utility of both speedometer shapes (full and half circle),
optimal level of speed readout resolution, and potential utility of dynamic speedometer features.
The study has several limitations to generalize the results and to be addressed in future studies. First, the fidelity
of driving simulation and equipment used in the study were still low so that more elaborated performance
measurements were limited. Therefore, it is required to conduct study under more realistic driving environment
including simulator and speedometer prototypes, whilemeasuring various driver performance, such as driving
performance (lane/speed keeping and variations), numbers/types of errors in driving or reading, accurate eye
attention profile to indicate driver’s eye distraction, and other physiological measures, when using the speedometer
during driving. Second, the sample of drivers was limited. Even though the statistical power in the results of study
were acceptable (note: detailed power analysis results were not presented in this paper due to page limit), various
driver characteristics such as age and background (e.g., potential driver stereotypes) were not investigated.
Therefore, it would be interesting to evaluate the effects of driver characteristics on the performances for various
types of flexible speedometer design, related to driving safety.
Based on this study, it is expected to conduct more research to generate insights and guidelines for designing
future speedometer in a flexible/configurable instrument cluster to improve driving performance and safety.